The problem with pectens is the same as with other families...the
inconsistancies in following the same critiria for speciation.  There are
literally hundreds of names of cones, cowries, turrids, etc. which
would be invalidated if the same rules had been followed for each and
every one.  There are more morphologic consistancies between G. pallium
and speciosa than more cogeners of Conidae.  Habitats of the former do
overlap.  And after examining hundreds...nay, thousands...of specimens of
both species in all stages of growth, I disagree with the conclusion that
they're one and the same.
 
But then, that's just my opinion...I could be wrong.
 
Kim Hutsell